Proprioception refers to the ability to know where a body part is located in space and to recognize movements of body parts (such as fingers and toes, feet and hands, legs and arms). Kinesthesia is a related term, and refers to the sensation by which position, weight, muscle tension and movement are perceived. In some of the medical literature, proprioception refers to the conscious and unconscious appreciation of joint position, while kinesthesia refers to the sensation of joint velocity and acceleration. Proprioception is often used interchangeably with kinesthesia, and herein as well, the terms will be used interchangeably.
U.S. Pat. No. 6,979,287 to Elbaz and Mor describes novel proprioceptive and kinesthetic exercise apparatus, which provides significant advantages over other prior art apparatus, such as tilt boards or shoes with a single protrusion. The apparatus includes two bulbous protrusions protruding from the underside of footwear, instead of the single ball of the prior art boards and shoes. One of the protuberances is positioned more posteriorly than the other protuberance. The extra protrusion may significantly increase the possibilities and enable walking, and accelerate and improve the results of proprioceptive and kinesthetic treatment plans.